Surface marker analysis of the vascular and epithelia lesions in cattle with sheep-associated malignant catarrhal fever.

Surface marker analysis of the vascular and epithelial lesions in cattle with sheep associated malignant catarrhal fever (MCF) were done by immunohistochemistry using 7 monoclonal antibodies. MHC class I and II antigens were expressed in the degenerated portion of the vascular walls in addition to infiltrated leukocytes. The major population of mononuclear cells in these lesions were phenotypically macrophages. The other cells had BoCD4 or BoCD8, but rarely gamma delta T cell markers. These results suggest involvement of MHC restriction and macrophages, in addition to autoaggressive cytotoxic T lymphocytes, in the development of MCF vascular lesion.